1. Field of the Invention
The present invention relates to a communication control method for controlling an ad hoc network formed by a plurality of mobile terminals, and a controller apparatus and a mobile terminal used in the communication control method.
2. Description of the Related Art
An ad hoc network formed by the configuration of a number of mobile terminals connected to each other without access points therebetween, using a wireless technology such as IEEE 802.11x or Bluetooth (registered trademark), has been known. Communication between mobile terminals forming such an ad hoc network is performed through a plurality of relay mobile terminals, or multi-hop.
In the ad hoc network, a reduction in the transmission power of a source mobile terminal reduces interference with communication of other mobile terminals, thus improving overall throughput in the ad hoc network, while it increases the number of radio links through which the communication between the mobile terminals is routed (hop count), thus increasing delay time in the communication between the mobile terminals.
On the other hand, an increase in the transmission power of the source mobile terminal reduces the number of radio links through which the communication between the mobile terminals is routed (hop count), thus reducing delay time in the communication between the mobile terminals, while it increases interference with communication of other mobile terminals, thus lowering overall throughput in the ad hoc network.
Accordingly, in the ad hoc network, overall throughput in the ad hoc network and delay time in communication between mobile terminals are in a trade-off relationship.
A conventional ad hoc network, however, has the problem that it cannot perform communication control, taking a trade-off relationship between overall throughput in the ad hoc network and delay time in communication between mobile terminals into account, though traffic distribution in the ad hoc network constantly changes, depending on the location distribution of mobile terminals, traffic conditions (such as a traffic volume) at each mobile terminal, and so on.